Four-wheel-drive transmission for tractors



R. L. TOLSON Original Filed Feb. 8. 1!

FOUR-WHEEL DRIVE TRANSMI SS ION FOR TRACTOR'S July 12, 1927;

gnaw/14hr John wfilrleg; Administrator of the state 0f Robert L asm gmsed. V -7 an we? rmsa' 1.1, 12. 1921.

. UNITED STATES PATENT OFFICE,

nom'r I4. 1015801, D, LATE OI KEIPHIS, TENNESSEE; BY JOHN w. FABLEY,

ron, or-xmrrms, racers-n, ormrrns, 'r :as 1;.

TENNESSEE, ASSIGNOR TO JOHN W. BAILEY, I

TRANSMISSION FOR TRACTOBS.

Original application illed'leoruary 2, 1821, Serial No. 441,915. Divided and this 'app1ication,flled lay r '88, 1928. Serial No. 640,795.

Referring to the accompanyin drawin which is made a part hereof an on whic similar reference Figure 1 is a (plan-view of my invention. Figure 2 is a etailed section through the difierential gearing.

In the drawing reference character ,in- 'dicates the body of a tractor having front wheels 11 and rear wheels 12. An engine on the frame has fixed to its shaft a gear 13 driving a gear 14 loose on a shaft 15 and the gear 14 drives a drum 16 by means of a ring 5 of gear teeth 17 midwa between the ends of the drum. The drum rives power operated steerin mechanism for the tractor in amanner f explained in the application above referr to. so A gine shaft rearwardly of the gear 13 and is 7 adapted in one position to drive a sprocket engaging a cham 19 which passes over another sprocket adapted to be connected to 88 the shaft 15 or to a rearwardly extendin shaft the transmission casing 20 in whic 1 is provided a differential which may be operated to drive the shafts connected to the differentials 23 and by means of hand levers '21 and 22 respectively. The details of the transmission mechanism are like those in Patent No. 1,437,692 December 5, 1922, the arrangement being such as .to drive the shafts differentially, or to drive either-one positively so that according to the" desire of the operator the front wheels alone may be driven while the rear wheels are idle, or the a rear wheels alone may be driven while the front wheels are idle.

When the front wheels are driven it is possible a drive both .of said wheels laced in orcharacters indicate similar lutch member 18 is splined 'to the en-.

or to drive either one positively while the other one is idle, this being due to a differtial gearin'g in a casing 23 such difierential gearing being controlled by hand levers 24 and 25 either to drive the beveled gears 26 and-27 differentially or to drive either one positively, said gears being connected, to drive the respective wheels in a manner fully explained'in the application above. referred to.

The drive of the rear wheels is controlled in similar manner, these wheels being driven from beveled gears 28 and 29 driven by a differential gearing in the casing 30 and the drive being controlled by hand'levers' 31 and 32 so as either to drive the two wheels differentiall or to drive either" one positively a8 desire while the other is idle.

Referring to Figure 2, the outer difierential casing is of conventional form for the usual purpose. A pinion 33' on a driving shaft 33 engages with a master gear 34 on the differential casing 35. This casin carries a series of pinions 36, 36 normal y engaging gears 37, 37. Each of the gears 37 37 has integral therewith a sleeve 38 surround-- ing a shaft of the divided axle 39 and splined thereto. An enlargedportion of each sleeve has gear teeth 40 formed thereon and each sleeve has also a groove engageable by a lever 41 pivoted at 42 on the gear casing and held in position by a pawl 13 and rack 14.

As shown in the drawing shaft 33, throu h the difi'erential mechanism, may drive sha s 39,39 in the usual fashion if desired. Alternately, either shaft 39 may be driven ositively by actuating its lever 41 to move s eeve 38 toa position in which the teeth 40 will engage teeth 43 on the difierential casing. It will be evident that when thus moved the gear 37 will be out of engagement with the could he so spaced as to afiord'an intermediate position in which neither set of teeth on a gear would he in engagement and no drive would he transmitted, a third notch being then provided on the se eat 44.

The operating levers for the clutches are shown extending laterally in order to show their manner of operation although obviously, they might extend vertically as shown in Fig. l.

lit will be seen from the above description that the diflcrential gearing enables the o erator to drive both sets of Wheels positive y from the engine or either set positivel when for example the other set is in a s ippery place. Alternatively both sets may be free from. the engine to permit the tractor to be pulled by propelling means other than its own power, if desired. It is also possible to drive any one Wheel by itself or any two or three Wheels as desired.

It will be obvious to those skilled in the art that this construction may he chan ed in numerous Ways and therefore it is not esired to limit the invention to the specific mechanism shown in the drawings and described aeaeeae in the specification but only as indicated in V the appended claim.

' Having-thus fully described said invention, what is claimed as new and desired to be secured by Letters Patent, is:

J In a motor-vehicle, front and rear Wheels,-

gear and adapted to drive the steering mechanism set forh.

In Witness whereof, I have hereunto set my hand at Memphis, Tennessee, this lath day of May, A D, 1923;

JOHN vvv renter, Admz'miatmtor of the Estate of Robert L,

Tulane, Deceased.

of the tractor, substantially as 

